Typewriter rhythm recorder



Nov. 18, 1947'. l T JACKSON` :2,431,043`

u TYPEWRITER RHYTHM RECORDER D IVER DIRTY EIGHT ENT RL/CRUET CUBIT FRUIT v `ATTORNEY I NOV. 18, 1947. C, T- JACKSON i 2,431,043

TYPEWRITER RHYTHM RECQRDER Filed Jn. 20, 1944 2 Sheets-Sheet 2 ATTORNEY Patented Nov. 18, 1947 TYPEWRITER RHYTHM RECORDER Carlton T. Jackson, Rochester, N. Y., assignor to International Business Machines Corporation, New York, N. Y., a corporation of New York Application January 20, 1944, Serial No. 518,985

8 Claims. (Cl. ,2M-5.8)

This invention relates to typewriting machines.

A broad object of the present invention is to provide a typewriter suitable for use in the teaching of touch typewriting.

An object is to provide a typewriting machine which may be used to discover faults in typewriting, such as lack of rhythm in the operation of the keys of a typewriter.

An object is to provide a typewriting machine with means to show typists faults graphically.

An object is to provide a means of tracing, in juxtaposition to the characters or spaces of aline of typewriting, graphic representations which enable the teacher of touch typewriting to detect erratic operation of the typewriter keys.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is a perspective view showing the present invention attached to a standard typewriting machine;

Fig. 2 is a vertical section on the line 2-2 in Fig. 1;

Fig. 3 is a top View of the tracing means;

Fig. 4 is a front view of the tracing means;

Fig. 5 is a vertical section on the line 5-5 of Fig. 1;

Fig. 6 is a specimen showing the graphic representations which are produced by the device in juxtaposition to the printed characters.

The present invention has been shown in the drawings and will be described hereinafter as applied to the well known Electromatic typewriter, formerly known as the International It will be understood, however, that the invention is not restricted in its application to the typewriter shown, or even to a power operated typewriter, but may be applied to wholly manually operated typewriters, since the mode of attachment of the means for tracing graphic representations is simple and may be readily eiected for any well known typewriting machine,

In Fig. 1 the typewriting machine base I0, the keys I I, the type bars I2, the front cover I3, and the platen I4 are shown. The type bars, as usual, are guided to the printing point by a type guide I5 (Figs. 1, 2 and 4) on the back of which is vertically slidably mounted the usual ribbon guide and vibrator I 6. This ribbon vibrator is automatically raised each time a character is printed by the type bars I2 through suitable universal bar mechanism not shown. However, in the well known Electromatic, ordinarily the ribbon vibrator is not operated when the space bar II (Fig. 1) is used to space between words and other characters where spacing is required.

The means for tracing graphic representations is supported by the front cover I3 (Figs. l to 4) and is carried by a post I8 removably secured to the cover I3.: Pivotally mounted on the post I8, as by means of the rod I9, is an arm 20 which extends rearwardly of the post and to the left to a point close to the platen I4, as most clearly shown in Fig. 2. The arm 20 is formed with an extension or side arm 20a which has a hole loosely supporting a suitable pen 2I which conveniently may consist of an ordinari7 fountain pen.

The spring 22, anchored to a lug formed in the main part of the arm 20 and to a ring 23 slipped over the tapered end of the pen 2 I, tends to press the pen toward the platen. The nibs of the pen project into an inclined oval hole 24a (Fig. 4) of a lever 24 pivoted at 25 in a slot in the arm 2U located just above the printing point and approximately tangent to the platen as most clearly shown in Fig. 2. The lever 24 is urged in a clockwise direction (Fig. 4) by a spring 26 which is anchored to a lug formed in the extension arm I8a of the post IB. The spring 26 also urges the arm 20 in a clockwise direction (Fig. 3) into engagement with a stop screw 2'I carried by a second extension arm Ib of the post I8. The stop screw 21 is adjusted so that the arm 20 and lever 24 adjacent the platen is clear of a sheet 28 (Fig. 2) wrapped around the platen.

On account of the fact that the usual paper bail cannot be used, the end of the arm 20 adjacent the platen is formed with a concave cylindrical surface 20h which is concentric with the axis of the platen I4 and acts as a guide to hold the sheet 28 wrapped around the platen. The arm 20 is also somewhat triangular shape at its end when viewed in plan, as best shown in Fig. 3 at 20c, to guide the edges of the sheet 28 underneath the end of the arm in the event the carriage is moved a little too far to right or left so that the edges of the sheet 28 parallel with the line of feed pass the printing point on either side and bulge away from the platen. 'Ihe right hand wall of the slot in the arm 20 receiving the lever 24 acts as a stop to restrict clockwise movement of lever 24, as most clearly shown in Fig. 4. The arm of lever 24 having the hole 24a extends downwardly so that the nibs of the pen 2I normally occupy a position a little above the printing point with the edge of the lever 24 just clear of the type elements when in printing position to prevent said elements from striking said lever.

A little to the right of the printing point, the lever 24 is formed with a shoe 24h which extends radially away from the aXis of the platen to a 5 point just over and in the path of the ribbon vibrator I6 in which is guided the usual inking ribbon 29. TEach time latype barisoperatedy-the .y f ribbon vibrator =|6 is raised-r simultaneously.- with the movement of the type bar to the printing 10 position and in its movement upwardly the ribbon vibrator engages the shoe 24h and rocks the lever 24 in a counterclockwise directionagainst-- the tension of spring 26. This..c auses,.the pen.. 2l to trace an inclined loop k'1.l zf. ,(Figv, LQ) ,..over-f15 every character printed but no suchloopris traedp.; when the space bar is operated since the ribbon vibrator, as aforesaid, does not operate except-- when a character is printed.

It will be understood r,that the machine is equipped with the` usual Y.carriagefeedingpower. spring and carriage.. ,r.eturn..mechanism....,. Tn'ei- Y escapementmechanism is removed .or released.. in some .convenient-,way as .byltymgdown 'the' usual carriage release levers... i 2

Means is providedto compel ,the carriage ie ed ing spring to feedthecarriageat a uniformrate. of speed instead of intermittently as wouldbe the'. casel ordinarily with. the, .escapement mechanism in use. This means lissliown in Figs-..1 and .5, and ,30 includes a rack., 3,0 which isy preferablylremovably .g attachedat its left hand .end (Fig.Y l.) yto ltl'ieright hand sideplateof the .carriage..The' rack 3ll j, preierablyiormed `of an angle, ,str.p yalong one edge. of which ,theteeth 3a are. cutwhich1mesh 35 with'a pinion 3l '(Fig. 5) on ajpinV 32. 1

The pin 32 is. pressedinto. .a .horizontalhole .in a block. 3,3 securedl to a plate .3.4 whichA maybe L fastened in any. suitablemannerjo thesurface...., of the. desk or .tablesupnorting ,the ,typewriting 40 machine or may formpart of a pla te or bracket .1. secured in s ome .suitablegfashionto thebase, ,I0 of the., machine. ,The '.upperend of block. 3.3 is cut` .witha horizontal rectangular slot33aLiFig`s; l and,5) twhich, receivesa block- 35 'slotted pt o 45 accommodate. therack and.. alsoiormed, With a cylindrcahspace. 35a .'jto -accommodate j thejA pinion 3,1.; ,Thei'pin .3.2 .lsolxtendsthroughrb` holen thelv block-35 registering withthe; hole vin the block 33carrying thepin 32, 'as clearly shownH 5o in Fig; 5. .A slot in the vblock 35 accommodatingfw` therackl) andthe bottom wall ,of the' slot.133'""' in the..block.33 act as a guideiorthe rack30.

Loosely mounted on ,the 1pin ,32, btween .the pinion 3| and -the. collarg36 on the pin3 2 is a. 55 pulley 31., Thislpulley31 is; connected by fa: belt 38 to a .suitable .driving motor .M Q the adjustable speed, .constant speed type having suitable. reduction gearingin which means is providedf or enabling theoperatonto adjust thejspeed to' any 60 desired value This motortendsto drive-'the pulley 31 in the direction of thearrow (Figi-1), thatjs, in thesamedirectiongas the 'pinion 3l i willbe turned when the typewriting machineis. moved in a letter spacing; directionby thepowerf) Sprngl.

The A pinion .3l is formedirorn ;a. bushing'` o r sleeve which extendsexternally 4vof the` blocks. 33 and .35 through. a. suitablelboreaor opening 3411. largev enough -to accommodatethe .pinion..3.l and has -wrappedfaround ita coil spring. 3 9,..oneA end..l of which..extends.radiallyof the 1pin32 andds hookedaroundastud 3Taarriedlbythepulley 31..

Preferably,"thef--spring- -39 is .coiled--a trieiaf smaller .thanwthez shank `of .the.,pinion 3l Vand .T15

pressed on the shank so that when the pinion 3l is rotated with the carriage travelling in letter spacing direction, the shank of the pinion tends to wrap the spring 39 more tightly around the shank of the pinion and thereby tends to turn the pulley 3l through pin 31a. When the carriage is returned, however, the pinion 3| rotates in the'reverseA direction and tendsto loosen the spr-ing 33 :allowing the shank, of theqpinion to turn loosely. In other Words, the spring 39 acts as an overrunning clutch connection between the pinion 3| and the pulley 31. The effect of this construction is that when the motor is driving the pulleyi at aspeedlower than the pinion 3l tendsto rotate while-the carriage is letter spacing; the'tplngtl acts-,as a restraining means and prevents the pinionfrom being rotated faster than thepulley 31 is driven by the motor whereby the driving: connections shown in Fig. 5 act as a brake and prevent the carriage from travelling faster ,in letter spacing Adirection .than a prede-f. termine'd rategdependingupon the .speed adiust-r ment of the motor;

When the' carriage is returnedinthejlsual way,-..

5 rack 33 is thrust to the right, (Fig;11,), or rearr."

wardly 'o f the planeef FlgL5, and the shank of pinion 3l rotates idlyi'n theV coiled part of spring.. Stand little obstruction is offered to the return` ing carriageexcept by the .tension of the power. spring.' i

Pulleyl] turned slowly v.by .the motor ,but the.' powerspringtends to driVetheQpuIley fasten... than thernotor. The power spring. howeven'is, not powerfuLenoughto `drive pulley 31"faster. -than the motor )since Athe mechanical .advantage of the belt drive and .the reduction gearing ormf.. ingv part of the motor is one. of speedrather .than forcefconsidering the power springlas theactual driving. means and thedriving motor'A and thei., Iparts shownin Fig."5 maybe .regarded as funcn tioning likea centrifugally actuated brake "having means to adjust the brake manually to regui late theV speed of the carriage.,

It is quitejclearn that. lby vsuitably,adjusting4 the. speed of the' motor the speed of carriage may.. v be adjustedtothemapabilitiesl of the operator.

At the end of each line the carriage is returned..-.t and the platenlinespacedin thensual way,.the.; line spacingnperation `taking placefirst...t This., .'.causesthe .pen .2l to trace-a lineAD '('Fig 6) joining the end of one line to theend of the next. linel :and .extendingalmost vertically .dow'nerr wardly.`,. When .the carriage returns ahorizontal' line 4l is traced which `conveniently servesas a. reference4 or base line along which time' intervals.; betweencharacters maybe measured with a suit-f. able .scale if. necessary., A Of course, Aafter. return ing -the carriage, Vtheoperator ,proceeds to typ'e, n andior eachcharacterprinted a loop 4l1"is formedcdirectly above the printed characterand. .l starts Afrom thebase line 4 IY tr'aced duringithe precedingparriagereturn operation andreturnsA to said` line.A

If the keysareoperated with an Yeven rhythm,A as in the `caseof thekeys for Atlzierst three 'let-j ters of the' word DIVER in the top` line of Flg 6, the loops Zia will all be uniform in heightgli. shape, and spacing, and willstart. and ,nis`h. on baseline 4l. lf the operator hesitates'too much or is too slow in operatingtwo successive1key`s;,-. the loopsflar will be spaced further .apart as at .l pointlb. At thispoint, theA operator-.hasabeenma too slowin operating the fE `-keywith the .resultthat ther pen'has retraced vpart of its .path alongwzf. the Abaselinelll .fora distanoedalmost-haltethe; fr.

length of the part of the base line associated with the loop formed in writing the letter V. On the other'hand, if the operator actuates some keys too fast the printing cycles will overlap and produce the effect shown at 2le (Fig. 6) which arose from too hasty operation of the I. key in printing the word DIRTY on the first line. When the space bar is operated, the pen 2l is not actuated but retraces the base line di for a distance which will depend upon the gap in time between completion of the operation of the type bar for the last letter of a word and the beginning of the operation of a type bar for the rst letter of a new word as indicated at 2id in Fig. 6. Here the length of the gap measured along the base line 4| as compared with similar gaps will indicate lack of rhythm in operating the space bar.

When an even rhythm is reached, the gaps 2id should be of uniform lengths and the loops Zla should all be nearly uniform in shape, spacing, height, and distance apart.

In the case of a power operated typewriter such as the one disclosed, each type bar has a denite operating time for each cycle and with a properly adjusted machine the operating cycles are approximately equal for all type bars for each speed adjustment of the machine, such machines usually being provided with a means to adjust the force of the blow of the type bars by adjusting the speed of the driving motor. Thus each ci the loops 2Ia should be substantially identical in shape for all type bars and, when a condition like that shown in Zlc is observed, it indicates that the type bars are overlapping in their cycles to an extent which may cause collizion between a restoring type bar and one on its printing stroke. When the loops are evenly spaced, as in printing the letters DIV of DIVER in the top line 0f Fig. 6 it indicates that the operator is closely following the capacity of the machine to print without overlapping the cycles of operation of the type bars to an extent to cause erratic spacing of the characters. rThis frequently is a difficulty of beginners particularly in learning to-operate manual typewriters because of the fact that some key combinations are much easier for some operators than others on account of varying degrees of dexterity of the fingers, left handedness, etc.

In the normal operation of a standard typewriter, where the carriage feeds only when a type bar is operated, the fault of rhythm consisting of too much time elapsing between successive impressions will not be evident since the carriage will space and stop between letters and it is immaterial how long the operator delays depressing the neXt key so far as the appearance of the work sheet is concerned. A fault of this kind is quite diicult to detect in a fast operator, even with Very close observation of the ngers.

The opposite fault of rhythm, on the other hand, shown at Ele (Fig. 6), is very easy to detect, particularly with power operated typew writers, because it causes overprinting of chare acters or too close spacing on the left hand side and not enough on the right hand side of thc second of three successive characters. However, the loops or graphic representations 2id, being very uniform in shape and size as compared with letters having varying widths, shapes, and sizes, are a better means of determining how bad the second fault of rhythm may be in each case.

The printing of the characters below the graphic representations shows clearly which key combinations are difficult for a particular oper ator and show which fingers require special .key exercises to cure the faults. Even without the printed characters, however, the invention is still useful since the printed characters are needed only to localize the faults of rhythm in the operators fingers by reference to the keyboard.

In the machine of the type disclosed, the uni versal bar which actuates the ribbon vibrator, as in most commercial machines, begins to move the ribbon vibrator when the type bar starts toward the printing point so that the ribbon vibrator, and hence the pen lil, travel at a rate proportional to the velocity of the type bar. Thus theloops 2Ia are also graphical representations of the operating cycles of the type bars and it is possible to detect faulty type bar operation by comparing the shapes of the loops made bydifferent type bars, particularly with the ones known to be striking properly.

While the pen 2l is shown as actuated by the ribbon vibrator as a preferred form involving the least alteration of the machine, it will be understood,V that any suitable means for actuating automatically the means for producing graphic representations of the characters are contemplated as within the scope of the claims.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a single embodiment it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. In a typewriting machine, in combination with the platen; means for typing a line of characters on a work sheet on the platen, a ribbon vibrator, means to feed the platen in a letterspacing direction and at a constant rate of speed while the typing means is typing a line of characters on said work sheet; and means actuated by the ribbon vibrator for tracing directly above each character in said line a curve forming a graphic representation, said representations by their shapes, spacing, and distances apart indicating faults in typing,

2. A typewriting machine having a platen, means for typing a line of characters on a work sheet on said platen, means to cause the platen to feed in a letter spacing direction at a controlled and uniform rate of speed while said line is being typed; and means controlled concomitantly with the typing of said characters for tracing a line of graphic representations, said representations by their shape and spacing marking the typists rhythm in juxtaposition with the typed line.

3. In combination with the platen, carriage, and typing means of a typewriting machine; a tracing pen disposed in front of the platen so as to trace above each character typed on a record sheet carried by said platen a representation, means controlled concomitantly for actuating said tracing pen each time a character is typed, and means to feed the carriage at a uniform rate to enable the spacing of the representations to denote the rhythm of the typist in writing a line of characters.

4. In combination with the platen, carriage, and typing means of a typewriting machine; a record sheet support, means controlled concomitantly; with the vtyping means in' typing aline of characters on the record sheet carried by said support,v tov trace on said sheet a line of representations, and means to feed the :record sheet support to spacesaid representations and characters apart in proportion to the elapsed` time between impressions.

5. In. combination with the carriage, of a typewritingmachine; means to type a line of characters on a record sheet. on the carriage; andmeans controlled concomitantly withk the; printing of each character to trace on said record sheet, a graphical representation in juxtaposition with the latter, said tracing means beingoperative to trace a base line for said representations when saidrcarriage is returned at the end of a line.

6.*In combination With the carriage of a typewriting machine, means to type a line of characters on a Work sheet on the carriage, a ribbon vibrator; and meansy actuated by the ribbon vibrator for tracingabove each character printed afrgraphical representation and operative when the carriage is returned to. .trace abase line for the graphicalrepresentations. on the; next line to be'ztyped;

7. In combination withythe .carriage of atypewijting machine, means to4 print characters on a work. sheetA carried by said carriage, `a ribbon vibrator; means to feed the; carriage in a letter spacing` direction at a uniformv rate of speed WhileA said characters are being printed, and a tracing pen mounted independently of thecarriageand having# its point coacting' with the record sheet and actuatedrbyfsaid ribbon'vibrator to trace graphical representations in juxtaposition to said characters, said pen remainingimmovable while the carriage is returned sod as to trace a base line for said representations.

8. In combination with character typing means: means for making a graphic representation, including a tracing pen adjacent the typing point, a record sheet support, means controlled concomitantly with said character typing means to move said pen in one direction, and means to effect a relative movement between the pen and a record sheet on said support at an angle to the rst direction While typing the characters on said record sheet, said movements coacting to trace a curve on said sheet in juxtaposition toA each character.

CARLTON T. JACKSON'.

REFERENCES CITED The following references are of record in the Iile of this patent:

UNITED STATES. PATENTS Number Name Date 474,773 Erickershoff et a1. May 10, 1892 1,253,305 Tulloss Jan. 15, 1918 1,399,429 Hulit Dec, 6, 1921 2,067,185 Green Jan. 12, 1937 2,337,553 Hofgaard Dec. 28, 1943 734,937 Peck July 28, 1903 840,554 Briggs Jan, 8, 1907 1,397,740 Pereira Nov. 22, 1921 1,651,102 Peiseler Nov, 29, 1927 2,348,744 McMurry May 16,l 1944 

